Override ARP Configuration

About this task

Address Resolution Protocol (ARP) is a protocol for mapping an IP address to a hardware MAC address recognized on the network. ARP provides protocol rules for making this correlation and providing address conversion in both directions.

When an incoming packet destined for a host arrives, ARP is used to find a physical host or MAC address that matches the IP address. ARP looks in its ARP cache and, if it finds the address, provides it so the packet can be converted to the right packet length and format and sent to its destination. If no entry is found for the IP address, ARP broadcasts a request packet in a special format on the LAN to see if a device knows it has that IP address associated with it. A device that recognizes the IP address as its own returns a reply indicating it. ARP updates the ARP cache for future reference and then sends the packet to the MAC address that replied.

To configure or override ARP configuration:

Procedure

Select Configuration → Devices from the web UI.
The Device Configuration screen displays a list of managed devices or peer controllers, service platforms, or access points.
Select a target device by double-clicking on the device name.
You can also select a target device from the lower, left-hand pane of the Web UI.

The selected device's configuration menu displays.
Expand Profile Overrides → Network and select DNS.
The selected device's DNS configuration screen displays.
Profile Overrides - Network - ARP Configuration Screen

Set the following ARP configurations:


Switch VLAN Interface	Use the spinner control to select a virtual interface for an address requiring resolution with the controller, service platform or access point.
IP Address	Define the IP address used to fetch a MAC Address recognized on the wireless network.
MAC Address	Displays the target MAC address subject to resolution. This is the MAC used for mapping an IP address to a MAC address recognized on the network.
Device Type	Specify the device type the ARP entry supports. Host is the default setting.

To add additional ARP settings select + Add Row and enter the configuration information.
Click OK to save the changes.
Click Reset to revert to the last saved configuration.